The present invention relates generally to a chopper device that distributes fiber material into a stream of resin material dispensed from a spray gun. More particularly, the present invention relates to a blade assembly used in the chopper device.
Chopper guns are frequently used in the composite material industry to form large, shaped products, such as in the marine and watercraft industries and pool and spa industries. Chopper guns include assemblies of a fiber chopper and a liquid spray gun. Compressed air is typically supplied to an external pump with a pumping mechanism and to an air motor in the fiber chopper. The pumping mechanism typically delivers a liquid resin material and a liquid catalyst material to the spray gun. Actuation of a trigger on the gun dispenses the materials into a mix chamber before being sprayed out of a nozzle of the gun. Mixing of the catalyst with the resin begins a solidification process, which eventually leads to a hard, rigid material being formed upon complete curing of the materials. The fiber chopper is typically mounted on top of the spray gun. The fiber chopper receives rovings of a fiber material, such as fiberglass, which passes between an idler wheel, an anvil and a cutter blade head. The fiber rovings are cut into small segments between the anvil and cutter blade head while being propelled out of the chopper by rotation of the anvil and the cutter blade head. The segments of fiber are mixed into the sprayed mixture of resin and catalyst such that the final cured product is fiber reinforced.
The blade head and anvil of the fiber chopper include consumable pieces that must be replaced after a threshold wear level is surpassed. For example, the blade head typically includes a plurality of razor blades inserted into slots on a blade wheel. Also, the anvil includes a roller of soft material into which blades of the cutter blade head penetrate while slicing or chopping the fiber roving. Thus, it is necessary to frequently disassemble the fiber chopper to access the cutter blade head and anvil, after which further disassembly of those components is also needed. In particular, it is necessary to remove the anvil roller and each blade of the cutter blade head. Prior art blade heads have involved using a blade bar and a wave spring that retains each razor blade within a slot of the blade wheel. This technique is tedious and labor intensive and provides higher risk to operators because handling of each blade is required when removing old blades and inserting new blades into the blade wheel.
There is, therefore, a need for a simpler system and method for retaining razor blades in a cutter blade head for a fiber roving chopper.